Device for recording centric jaw relation and orientation jaw relation simultaneously

ABSTRACT

The device for recording centric jaw relation and orientation jaw relation simultaneously is disclosed that provides an accurate and precise recording of centric jaw relation as well as orientation jaw relation recording and transfer. The device includes a central bar, a centric relation recorder, a dentulous adjustable fork or an edentulous fork, a semi-circular frame, a nasion pointer and an orbital pointer. The central bar is received by a plurality of clamping assemblies that adjustably position the nasion pointer, the adjustable fork or the edentulous fork and the centric relation recorder respectively. The device can be used in case of both, dentulous as well as edentulous subjects. The device can advantageously transfer the centric relation record to any semi-adjustable articulators or non-adjustable articulators.

CROSS REFERENCE TO RELATED APPLICATION

The present application is a divisional of U.S. patent application Ser.No. 15/319,709, filed on Dec. 16, 2016, and titled “A DEVICE FORRECORDING CENTRIC JAW RELATION AND ORIENTATION JAW RELATIONSIMULTANEOUSLY,” the disclosure of which is expressly incorporated byreference herein in its entirety.

TECHNICAL FIELD

The invention relates to a device for recording centric jaw relation andorientation jaw relation simultaneously and particularly to a device foran accurate and precise recording of centric jaw relation as well asorientation jaw relation recording and transfer and more particularly toa device for dentulous as well as edentulous subjects thatadvantageously guides the mandible such that, its condyle head achievesthe most superior and anterior position as per the latest definitiongiven in Glossary of Prosthodontics Terms (GPT)-8.

BACKGROUND

Centric jaw relation (CR) is a complex and controversial concept indentistry. Main reason for the controversies is because its definitionchanged many times during last ten decades. Position of the head of thecondyle during centric jaw relation position is the reason for most ofthe controversies. With the advancements in the field of oral radiologynow it is understood that the head of the condyle does not attain mostretruded unstrained position but it attains most anterior and superiorposition in the glenoid fossa. Centric jaw relation remains complexbecause the latest Glossary of Prosthodontic Terms (OPT)-8 continues togive seven definitions for centric jaw relation and some of thedefinitions are contradictory to each other. Another reason is as perlatest GPT-8 the centric jaw relation definition, which is widelyaccepted, relates CR to so many clinically invisible parts making itdifficult for the operator to follow its description in clinicaldentistry. There is no device which will help the operator to guide thehead of the condyle to attain this position as per the description givenin the definition. Recording CR is very important step because it is theonly relationship of the mandible to the maxilla which is repeatable,reproducible and recordable.

CR is defined as per the latest GPT-8 and widely accepted, “themaxillo-mandibular relationship in which the condyles articulate withthe thinnest avascular portion of their respective discs with thecomplex in the anterior-superior position against the slopes of thearticular eminences. This position is independent of tooth contact. Thisposition is clinically discernible when the mandible is directedsuperiorly and anteriorly. It is restricted to a purely rotary movementabout the transverse horizontal axis”.

Apart from recording centric jaw relation other important relationshipof the jaws with the Temperomandibular joint (TMJ) which is known asorientation jaw relation which is to be recorded using a facebow.Maxilla is a part of the cranium and is a fixed entity when the teeth ofboth jaws come in contact; mandible gets related to the maxilla so thatthe entire craniomaxillary complex is articulated with a moving bone,which is the mandible. The maxilla is oriented uniquely to theTMJ/cranium and this positioning differs from individual to individual.The anatomy of maxilla and the temporomandibular joint varies fromperson to person. Recording of the opening axis of the patient and itstransfer to the articulator is very important for the occlusiondeveloped on the articulator to remain same when the prosthesis istransferred to the patient's mouth, is the logic behind recordingorientation jaw relation.

Centric jaw relation is an old concept in dentistry. There are over 26different definitions of centric jaw relation since 1926. It is aposition which is the only position of the mandible that is repeatable,recordable and reproducible. According to old definition of the centricjaw relation, the location of both condyles was considered to beattaining the most retruded position; however, now it is understood thatit attains most anterior and superior position in the glenoid fossae.The accuracy of recording is highly dependent on the individualunderstanding of the concept, skills, judgement, method chosen byindividual dentist, their experience, etc. Centric jaw relation is themandibular jaw position in which the head of the condyle is situated asfar anterior and superior as it possibly can within the glenoid fossa.

Dentists use various conventional methods and devices to obtain preciselocation and recording of centric jaw relation which includesphysiological methods like tactile or inter-occlusal check recordmethod, pressure less method, pressure method or functional methods likeNeedle-House method, Patterson method or graphic methods like intraoralmethod, extraoral method, and radiographic method. In order to recordthe centric jaw relation, it is important that both condyles be seatedin their most superior and anterior position in the glenoid fossae.However, there exists no single device or instrument to achieve aprecise location and recording of a centric jaw relation in edentulousand dentulous patients that can be accepted universally. There doesexist a precise single method, i.e., graphic recording which is mostcommonly used in edentulous patients with good alveolar ridges, howeverit has its own limitation and cannot be used for all the patients.

Similarly, the face bow transfer which establishes the relationshipbetween the maxilla and the TMJ, i.e., the relationship of the maxillato the opening axis so that the maxillary cast can be mounted on thearticulator in the correct anatomical position is another importantaspect in dentistry and face bow is a device that is used to record therelationship of the jaws to the temporomandibular joints or the openingaxis of the jaws and to orient the cast in the same relationship to theopening axis of the articulator. There are many existing face bowrecording devices for achieving the required face bow transfer. However,there is no single device in prior art that allows a combination ofcentric jaw relation recording and face bow recording and its transferin one sitting of the patient.

U.S. Pat. No. 3,643,332 discloses a method for measuring the movementsof the lower jaw (mandible) relative to the upper jaw by selecting twopoints at a fixed distance apart on the horizontal axis of rotation ofthe subject's mandible, one on each side of subject's head and atsubstantially equal distances from the subject's head. This prior artdocument allows only face bow transfer and does not record centric jawrelation.

Another patent document (European Patent No. EP950384) discloses anapparatus for tracing to record a centric jaw relation of a patient,particularly by a tracing apparatus in which a stylus is used to recorda centric jaw relation of a patient for the fabrication of a prosthesisor dentures is coupled to a nut-shaped ball supported by a base platemounted to a dentition and a support plate threadedly coupled to thebase plate in such a fashion that it can be selectively pivotable,thereby eliminating use of any separate dentition supporting wires.However, the disclosed apparatus may cause injury to the patient due tothe presence of the stylus and there could also be chances of unevenpositioning of the apparatus that would ultimately give inaccuraterecordings.

Another prior art document (U.S. Pat. No. 3,750,289) discloses thecentric jaw relation device that comprises of an upper frame and a lowerframe which are hinged together along the condylar axis by a joint whichpermits relative movement only by rotation in a medial plane. However,this prior art references can only be used in case of edentulouspatients and can only have its application in face bow transfer and notfor centric jaw relation recording per se. Further, the devices of theprior art have a complex structure, and may cause injury to the patient.These devices though may provide satisfactory jaw relation recordingsand face bow transfer, but require multiple sittings and appointments ofthe patients for face bow transfer and centric recording procedure.There is no device in art that provides both the procedures in oneappointment. Further, most of the prior art devices for recording ofcentric jaw relation can only be used in case of edentulous patients. Itis found that there has not been a single attempt to develop a devicefor recording centric jaw relation as per the latest definition as perGPT-8.

Thus, to achieve an accurate and precise centric jaw relation recordingas well as face bow recording and transfer or orientation jaw relationsimultaneously of subjects is an essential criterion for restoration offunction, facial appearance, and maintenance of subject's oral health.Inaccurate centric jaw relationship will eventually lead to failure of aprosthesis leading to re-fabrication, which is a time consuming and acostly affair. Therefore, there exist a need for a centric jaw relationrecording device that gives accurate recording of centric jaw relationand which allows orientation jaw relation as well, thereby avoidingmultiple appointments for the subjects and a device that is safe andthat can be used in both, dentulous as well as edentulous subjects.

SUMMARY

The present invention discloses a device for recording centric jawrelation and orientation jaw relation simultaneously of a dentuloussubject in a single step. The device comprises a centric relationrecorder that includes a calibrated rod, a calibrated slider and anarcuate grip. The calibrated rod includes a predefined first main scaleand the calibrated slider includes a predefined second scale thatrecords a centric jaw relation of a subject through the arcuate gripthereby adjusting the calibrated rod and calibrated slider. Thecalibrated slider is freely movable within the calibrated rod along apredefined axis thereof. A dentulous adjustable fork has a first curvedend and a second straight end, wherein the first curved end has a pairof arms attached at a predefined position to facilitate fastening of adesired recording material and the second straight end is attached tothe central rod. A first combination of reference points includes asemi-circular frame and a nasion pointer, wherein the semi-circularframe has two posterior points of reference and the nasion pointerdefines a first anterior point of reference. A second combination ofreference points includes a semicircular frame and an orbital pointer,wherein the semi-circular frame has two posterior points of referenceand the orbital pointer defines a second anterior point of reference.The nasion pointer and the orbital pointer alternately define a thirdpoint of reference. The third point of reference varies as persemi-adjustable articulator.

The centric relation recorder is a first recorder that records anaccurate and precise centric relation of jaw. The semi-circular framewith the two combinations of reference points is a second recorder thatrecords orientation jaw relation of the dentulous subject. The centricrelation recorder, the nasion pointer and the adjustable fork arepositioned on a predefined clamping assembly having a plurality ofscrews, a plurality of locks and a connector. The centric relationrecorder, the nasion pointer and the adjustable fork are perpendicularto the central bar. The centric relation recorder, the nasion pointerand the adjustable fork adjustably position at a predefined position onthe central bar thereby adjusting respective screws in horizontal,vertical, forward and backward movements thereof. The orbital pointerpositions at a predefined location on the semi-circular frame such thatthe semi-circular frame is parallel to the inter-pupillary line. Thedevice guides the mandible in such a way that the head of the condyle inthe glenoid fossa, along with its respective complexes attain mostanterior and superior position on either side, thereby resulting into anaccurate and precise centric jaw relation recording. The calibratedslider is fine-tuned until firm resistance is felt by an operator ofsaid device.

A device for recording centric jaw relation and orientation jaw relationsimultaneously of an edentulous subject in a single step comprises acentric relation recorder that includes a calibrated rod, a calibratedslider and an arcuate grip. The calibrated rod includes a predefinedfirst main scale and a calibrated slider includes a predefined secondscale that records a centric jaw relation of a subject through thearcuate grip thereby adjusting the calibrated rod and calibrated slider.The calibrated slider is freely movable within the calibrated rod alonga predefined axis thereof. An edentulous fork has a first curved end anda second straight end, wherein the first curved end has a C-clipattached at a predefined position to facilitate fastening to maxillaryand mandibular wax rims and the second straight end is attached to thecentral rod. A first combination of reference points includes asemicircular frame and a nasion pointer, wherein the semi-circular framehas at least two posterior points of reference and the nasion pointerdefines a first anterior point of reference. A second combination ofreference points includes a semi-circular frame and an orbital pointer,wherein the semi-circular frame has two posterior points of referenceand the orbital pointer defines a second anterior point of reference.The nasion pointer and the orbital pointer alternately define a thirdpoint of reference. The third point of reference varies persemi-adjustable articulator.

The centric relation recorder is a first recorder that records anaccurate and precise centric jaw relation of jaw. The semi-circularframe with the two combinations of reference points is a second recorderthat records orientation jaw relation of the edentulous subject. Thecentric relation recorder, the nasion pointer and the edentulous forkare positioned on a predefined clamping assembly having a plurality ofscrews, a plurality of locks and a connector. The centric relationrecorder, the nasion pointer and the edentulous fork are perpendicularto the central bar. The centric relation recorder, the nasion pointerand the edentulous fork are adjustably positioned at a predefinedposition on the central bar thereby adjusting respective screws inhorizontal, vertical, and forward and backward movements thereof. Theorbital pointer positions at a predefined location on the semi-circularframe such that the semi-circular frame is parallel to theinter-pupillary line. The device guides the mandible in such a way thatthe head of the condyle in the glenoid fossa, along with its respectivecomplexes attain most anterior and superior position on either side asdefined in GPT-8, thereby resulting into an accurate and precise centricjaw relation recording. The calibrated slider is fine-tuned until filmresistance is felt by an operator of said device.

A method for recording centric jaw relation and orientation jaw relationsimultaneously of a dentulous subject in a single step comprises thesteps of; making an occlusal jig in an acrylic resin or any othersuitable material thereby subjecting mandibular anterior teeth of thesubject in such a way that it disoccludes maxillary and mandibular teethduring all possible movements thereon. An adjustable fork is adjusted inbetween maxillary and mandibular teeth of the subject in such a way thatit does not come in between maxillary and mandibular teeth and a doublelayer of a preferred perforable recording material is wrapped onto theadjustable fork to support the recording material from sides. Asemicircular frame is oriented and stabilized along an anterior side ofthe subject's face thereby approximating an orbital pointer at apredefined level of subject's infraorbital notch or alternatively nasionpointer at a predefined position over nasion depending on thesemi-adjustable articulator being used. A centric relation recorder isfixed over the subject's chin by adjusting a predefined calibrated rodand a predefined calibrated slider. The readings on the calibrated rodand calibrated slider are noted and the above the step is followed atleast three times thereby keeping the occlusal jig in the predefinedposition. The adjustable fork and the centric relation recorder arepositioned back to the noted reading of above said step and the subjectis asked to bite the recording material in one go. The nasion pointer,adjustable fork and centric relation recorder are tightened byrespective screws for ensuring that the orbital pointer corresponds tothe infra orbital notch or alternatively the nasion pointer correspondsto the nasion to be used as the third point of reference. All therespective screws of the centric relation recorder and nasion pointerare loosened to remove the semicircular frame of the subject's facealong with the adjustable fork for and the recorded indentations arenoted on to the recording material. Said recorded indentations aretransferred to the semi adjustable articulator such that indirecttransferring of the recorded indentations or inter occlusal record isachieved by transferring inter occlusal record to the semi adjustablearticulator. The transfer is done using a transfer jig of thearticulator or said record is transferred to the semi-adjustablearticulator by a direct transfer.

A method for recording centric jaw relation and orientation jaw relationsimultaneously of an edentulous subject comprises the steps of: correctvertical jaw relation is recorded and it is ensured that there is no gapbetween maxillary and mandibular wax rims at occlusal verticaldimensions thereof. A semi-circular frame is oriented and stabilizedalong an anterior side of the subject's face thereby approximating anorbital pointer in a predefined position at a predefined level ofsubject's infraorbital notch or alternatively nasion pointer in apredefined position over the nasion depending on the semi-adjustablearticulator being used. A centric relation recorder is fixed over thesubject's chin by adjusting a predefined calibrated rod and a predefinedcalibrated slider. The readings on the calibrated rod and calibratedslider are noted and said step is followed at least three times.Further, a fork for edentulous subjects is designed, wherein a pin isinserted in maxillary and mandibular wax rims anteriorly along a midlinethereof. The centric relation recorder is placed back to the above notedreading and an edentulous fork is inserted in the midline in such a waythat it seals maxillary and mandibular wax rims together. Both the rimsare further sealed together additionally by stapler pins by placing iton either side buccally such that half of the pin is inserted into themaxillary wax rim and half of the pin is inserted into the mandibularwax rim. The nasion pointer, the edentulous fork and centric relationrecorder are tightened by respective screws such that orbital pointercorresponds to the infra orbital notch or alternatively the nasionpointer corresponds to the nasion thereby defining a third point ofreference. Further, all respective screws of the centric relationrecorder and the nasion pointer are loosened and the semi-circular frameis removed of the subject's face along with the edentulous fork havingsealed maxillary and mandibular wax rims. The recorded sealed wax of theabove step is transferred to the semi adjustable articulator either bydirect transfer or indirect transfer. After transferring centricrelation record and mounting of the casts to said articulator, theprotrusive record is recorded for adjusting the condylar guidance on asemi-adjustable articulator.

The protrusive record is recorded, wherein the mandibular wax rim isreduced by 2-3 mm in height, except in second molar region on eitherside and in the central incisors region to maintain the verticaldimension. Inverted ‘V’ shaped notches are prepared on the maxillary waxrim in premolar and first molar region on either side. Further, 6 mm issubtracted from said recorded centric relation reading when a firmresistance was felt by the operator in order to obtain a protrusivereading of an edentulous subject. In a further step the centric recorderassembly is fixed at above said predefined protrusive reading and therecording material such as plaster of Paris or any other suitablematerial is placed between the wax rims. The condylar guidance isadjusted according to said protrusive record and a lateral condylarguidance is adjusted by using Hanau's formula L=H/8+12. The device forrecording centric relation and orientation jaw relation simultaneouslyof dentulous subject also records either centric relation or orientationjaw relation separately as per the requirement. The device for recordingcentric relation and orientation jaw relation simultaneously ofedentulous subject also records either centric relation or orientationjaw relation separately as per the requirement. The centric relationrecord is transferred to any semi-adjustable articulators ornon-adjustable articulators in case of the device for dentulous subjectsas well as in case of device for edentulous subjects.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front perspective view of a device for recording centric jawrelation and orientation jaw relation simultaneously of a dentuloussubject in accordance with a preferred embodiment of the presentinvention;

FIG. 2 is a front perspective view of a first clamping assembly of adevice of FIG. 1;

FIG. 3 is a perspective view of a semi-circular frame of a device ofFIG. 1;

FIG. 4A is a perspective view of a third clamping assembly of a deviceof FIG. 1;

FIG. 4B is a perspective view of an adjustable fork of a device of FIG.1;

FIG. 5 is a perspective view of a fourth clamping assembly with acentric relation recorder of a device of FIG. 1;

FIG. 6A is a front perspective view of a device for recording centricjaw relation and orientation jaw relation simultaneously of anedentulous subject in accordance with a preferred embodiment of thepresent invention; and

FIG. 6B is a front a perspective view of a third clamping assembly of adevice of FIG. 6A.

DETAILED DESCRIPTION

Although specific terms are used in the following description for sakeof clarity, these terms are intended to refer only to particularstructure of the invention selected for illustration in the drawings,and arc not intended to define or limit the scope of the invention.

Referring to FIG. 1, a device 100 for recording centric jaw relation andorientation jaw relation simultaneously of dentulous subjects inaccordance with a preferred embodiment of the present invention isdisclosed. The device 100 for recording centric jaw relation andorientation jaw relation simultaneously includes a central bar 102,nasion pointer 104, a semicircular frame 106, an adjustable fork 108, acentric relation recorder 110 and an orbital pointer 112. The centralbar 102 is receivable by a plurality of clamping assemblies 114,116,118, 120. The clamping assemblies 114, 118, 120 adjustably position thenasion pointer 104, the adjustable fork 108, and the centric relationrecorder 110 respectively. The central bar 102 is normal to the groundin a direction indicated by axis-Y. The nasion pointer 104 is adjustablypositionable through a first clamping assembly 114. The semi-circularframe 106 is adjustably positionable on the central bar 102 through asecond clamping assembly 116 such that the semi-circular frame 106 ispositionable on the subject's face in accordance with the presentinvention. It is to be noted that the semi-circular frame 106 is made upof stainless steel that provides the property of spring action to thesemi-circular frame 106, thereby making the frame 106 self-centering.The second clamping assembly 116 attaches semicircular frame 106 to thecentral bar 102. The adjustable fork 108 is adjustably positionablethrough a third clamping assembly 118 and the centric relation recorder110 is adjustably positionable through a fourth clamping assembly 120.The first clamping assembly 114 clamps the nasion pointer 104 to thecentral bar 102, the second clamping assembly 116 clamps thesemi-circular frame 106 to the central bar 102, the third clampingassembly 118 clamps the adjustable fork 108 and the fourth clampingassembly 120 clamps the centric relation recorder 110. The nasionpointer 104, the adjustable fork 108 and the centric relation recorder110 are clamped such that the nasion pointer 104, the adjustable fork108 and the centric relation recorder 110 are positioned perpendicularto the axis-Y of the central bar 102.

The semi-circular frame 106 is attached such that the central bar 102 isanterior to the semi-circular frame 106 and the semi-circular frame ispositionable by the spring action of the semi-circular frame. Thesemi-circular frame 106 includes two extreme ends, a left end 106A and aright end 106B. The orbital pointer 112 is positionable at a predefinedposition on the semi-circular frame 106 in close proximity of the rightend 106B. The nasion pointer 104, the adjustable fork 108, the centricrelation recorder 110 are attached such that they are adjustablypositionable horizontally along a predefined axis through the clampingassemblies 114,118,120 respectively facing towards the two extreme ends106A and 106B of the semicircular frame 106 and are perpendicular to theY-axis of the central bar 102. It is to be noted that the device 100 hastwo combinations of reference points, wherein the first combinationincludes the two extreme ends 106A and 106B of the semi-circular frame106 acting as the two posterior points of reference and the nasionpointer 104 acting as a first anterior point of reference depending uponthe type of articulator used. Similarly, the second combination is thetwo extreme ends 106A and 106B of the semi-circular frame 106 acting asthe two posterior points of reference and the orbital pointer 112 actingas a second anterior point of reference depending upon the type ofarticulator used. The device 100 of the present invention includes apair of recorder, wherein the fourth clamping assembly 120 having thecentric relation recorder 110 acts as the first recorder for recordingthe centric relation and the semi-circular frame 106 along with eitherof the two combinations of reference points acts as a second recorderfor recording of orientation jaw relation of the dentulous subject.

Now referring to FIG. 2, a front perspective view of the first clampingassembly 114 of the device 100 for recording centric jaw relation andorientation jaw relation simultaneously for dentulous subjects isdescribed. The first clamping assembly 114 includes a plurality ofscrews, a plurality of locks and a connector for adjustably clamping thenasion pointer 104 to the central bar 102. The first clamping assembly114 includes a first lock 202, a second lock 204, a connector 206, afirst screw 208, a second screw 210, a third screw 212 and the nasionpointer 104. The central bar 102 is adjustably couplable to the firstlock 202 such that the central bar 102 is receivable within the lock 202and is tightened by the first screw 208. The nasion pointer 104 includesan L-bar 214 and an arcuate pointer 216. The L-bar 214 has two ends. Afirst straight end of the bar 214 is adjustably couplable in the secondlock 204 and a second curved end of the bar 214 is fixedly attachable tothe arcuate pointer 216 at a predefined position. A first end of theconnector 206 is horizontally couplable to the first lock 202 at apredefined position and a second end of the connector is receivable inthe second lock 204 such that the connector 206 is perpendicular to thecentral bar 102 and is fixedly attached to the second lock 204 bytightening the second screw 210. The nasion pointer 104 is clamped suchthat the pointer 104 is perpendicular to the Y axis of the central bar102. The nasion pointer 104 is adjustably moved in the forward andbackward direction such that the arcuate pointer 216 is fixed to thesubjects' nasion point that is over the nose bridge by adjusting thethird screw 212. The nasion pointer 104 is horizontally adjustable alongZ-1 axis at a predefined position either by loosening or tightening ofthe screw 210, vertically by adjusting screw 208, and forward orbackward by screw 212 to achieve a required nasion pointer 104 length.The required length of the nasion pointer 104 is achieved by forward,backward, vertical and horizontal movement of the L-bar 214 by looseningof the respective screws and the nasion pointer 104 is locked at apredefined position as required by tightening of the respective screws.It is to be noted that the position of screws of the first clampingassembly may vary in other alternative embodiments of the device 100 forrecording centric jaw relation and orientation jaw relationsimultaneously.

Referring to FIG. 3, a perspective view of the semi-circular frame 106of the device 100 for recording centric jaw relation and orientation jawrelation simultaneously for dentulous subjects is described. Thesemi-circular frame 106 includes a centrally positioned bush 302, ascrew 303, the orbital pointer 112, and a pair of ear plugs 304. Thesemi-circular frame 106 includes two extreme ends such that each of theends includes the ear plugs 304. The orbital pointer 112 is positionableat a predefined position on the semi-circular frame 106 in closeproximity of the right end. The semi-circular frame 106 is adjustablyreceivable by the second clamping assembly 116, such that thesemi-circular frame 106 is removably positionable in the subject's earsthrough the spring action of the semi-circular frame and is connected tothe central bar 102 through the clamping assembly 116, bush 302 and islockable by the screw 303. The semi-circular frame 106 is removablyattachable to the central bar 102 such that the central bar 102 isposterior to the semi-circular frame 106.

The orbital pointer 112 includes a socket 306, a pointer 308 and a bolt310. The socket 306 includes a central notch. The orbital pointer 112 ispositioned on the right side of the semi-circular frame at a predefinedposition such that the central notch of the socket 306 is fixed in thesemi-circular frame 106 at a predefined position. The pointer 308 isfixedly positioned on a top end of the socket 306 via the bolt 310. Thesemi-circular frame 106 is oriented along the anterior side of thesubject's face such that the pair of ear plug 304 is inserted into thesubject's respective ears and semi-circular frame 106 is parallel tointerpupillary line and the orbital pointer 112 is adjusted accordingly.The semi-circular frame 106 is stabilized over the subject's ears suchthat the orbital pointer 112 corresponds to the subject's infraorbitalnotch on the right side of the face as a third point of reference. Thesemi-circular frame 106 along with the two combinations of referencepoints is the second recorder for recording of orientation jaw relationof the dentulous subject. It is to be noted that the position of theorbital pointer 112 may vary in other alternative embodiments of thedevice 100 for recording centric jaw relation and orientation jawrelation simultaneously.

Further, referring to FIGS. 4A and 4B, perspective view of a thirdclamping assembly 118 and an adjustable fork 108 of the device 100 forrecording centric jaw relation and orientation jaw relationsimultaneously for dentulous subjects is described. The third clampingassembly 118 includes a plurality of screws, a plurality of locks and aconnector for adjustably clamping the adjustable fork 108 to the centralbar 102. The third clamping assembly 118 includes a first lock 402, asecond lock 404, a connector 406, a first screw 408, a second screw 410,a third screw 412 and the adjustable fork 108. The central bar 102 isadjustably couplable to the first lock 402 such that the central bar 102is receivable within the lock 402 and is tightened by the first screw408. The adjustable fork 108 includes two ends, a first curved endhaving a pair of arms 414 and a second straight end 416 adjustablycouplable in the second lock 404. The first curved end of the fork 108is adjustably attachable to the arms 414 at a predefined position. Afirst end of the connector 406 is horizontally couplable to the firstlock 402 at a predefined position and a second end of the connector 406is receivable in the second lock 404 such that the connector 406 isperpendicular to the central bar 102 and is fixedly attached to thesecond lock 404 by tightening the second screw 410. The adjustable fork108 is clamped such that the adjustable fork 108 is perpendicular to theY axis of the central bar 102. The adjustable fork 108 is horizontallyadjustable along Z-2 axis at a predefined position either by looseningor tightening of the screw 410, vertically by 408 and forward orbackward by 412 accordingly to achieve a required adjustable fork 108length. It is to be noted that the position of screws of the thirdclamping assembly may vary in other alternative embodiments of thedevice 100 for recording centric jaw relation and orientation jawrelation simultaneously.

The arms 414 are adjustably couplable to the first curved end of thefork 108 and are fixedly adjustable by a screw 418 and a plurality ofsupports 420 such that the supports 420 clamp the arms 414 and connectthe arms 414 to the fork 108, and the screw 418 adjustably tighten orloosen the arms 416 in a predetermined position. The pair of arms 414 ofthe adjustable fork 108 facilitates the fastening of a recordingmaterial. The recording material is a double layer of wax or any othersuitable perforable material. The adjustable fork 108 is insertable intothe subjects' mouth such that the pair of arms 414 does not interferewith the subjects' teeth while occluding.

The arms 414 are adjusted at a predefined position to achieve a requireddistance between the arms 414 without interfering the occlusion byadjusting screw 418. The arms 414 are lockable in a required positing bytightening screw 418. The required length of the adjustable fork 108 isachieved by forward, backward, vertical and horizontal movement of thestraight end 416 by loosening of the respective screws and theadjustable fork 108 is locked at a predefined position as required bytightening of the respective screws. It is to be noted that the arms 414of the adjustable fork 108 for dentulous subjects are customizedaccording to the width of the subject's arch and is designed to recordmaxillary and mandibular occlusal record without any interference of theteeth.

Referring to FIG. 5, a perspective view of a fourth clamping assembly120 and a centric relation recorder 110 of the device 100 for recordingcentric jaw relation and orientation jaw relation simultaneously fordentulous subjects is described. The fourth clamping assembly includes abush 502, a collar 504, a plurality of screws 505, 506, 507 and thecentric relation recorder 110. The centric relation recorder 110includes a predefined calibrated rod 508, a predefined calibrated slider510 and an arcuate grip 512. The centric relation recorder 110 isclampable to the fourth clamping assembly 120 such that the centricrelation recorder 110 is adjustably positionable to the central bar 102through the bush 502 that is connectable between the centric relationrecorder 110 and the collar 504, and the bush 502 is tightened to thecentral bar 102 by the screw 505. The centric relation recorder 110 isperpendicular to the Y axis of the central bar 102. The rod 508 ismovable along Z-3 axis and is adjustable at a predefined position by thescrew 507. The centric relation recorder 110 is assembled such that thearcuate grip 512 is fixedly attached to the slider 510. The rod 508receives the slider 510 such that the slider 510 is adjustable along theZ-3 axis by the screw 506 and is an integral part of the centricrelation recorder 110.

The slider 510 has a diameter that is less than the rod 508 such thatthe slider 510 is adjustable into the rod 508 along the Z-3 axis and isfreely movable inside the calibrated rod. The slider 510 is adjustablein the forward and backward direction at a predefined position either byloosening or tightening the screw 506 accordingly after positioningslider 510 accurately over the subject's chin. The slider 510 provides alinear motion to the arcuate grip 512. The rod 508 and the slider 510 ofthe centric relation recorder 110 are calibrated with a predefined scalefor the recording of the centric jaw relation. The calibrated rodincludes a predefined first main scale for recording of the centric jawrelation and the calibrated slider includes a predefined second scalefor fine tuning and recording of the centric jaw relation of a subjectby adjusting the rod at a predefined position by the arcuate grip and byfine adjustment done with the slider. It is to be noted that therequired major adjustment is done by adjusting the rod 508, followed byfine adjustment by the slider 510 by moving the screw 506.

The arcuate grip 512 is positionable over the center of the subject'schin such that the chin of the subject is in a relaxed position on thearcuate grip 512 of the centric relation recorder 110. The arcuate grip512 of the centric relation recorder 110 is fixed over the center of thesubject's chin and the major required length of the recorder 110 isadjusted by adjusting 508 and tightening the screw 507 and furtherlength can be achieved by tightening 506 until a strong resistance isfelt by the operator.

In accordance to the present invention, subject's anterior occlusal jigis to be made by either acrylic resin or any other suitable material sothat the subject's maxillary and mandibular teeth do not contact eachother during any movement of the mandible i.e., forward, backward andlateral etc. The centric relation recorder 110 is fixed over thesubjects chin by adjusting the rod 508 as much as possible to apredefined length to ensure that the reading on the slider 510 is zero.

In another embodiment, referring to FIG. 6A and FIG. 6B, a frontperspective view of a device 600 for recording centric jaw relation andorientation jaw relation of edentulous subjects and a perspective viewof third clamping assembly 618 of device 600 of the present invention isdescribed. In this another embodiment, the device 600 of the presentinvention is used in edentulous subjects. The device 600 for recordingcentric jaw relation and orientation jaw relation simultaneously ofedentulous subjects includes a central bar 602, nasion pointer 604, asemi-circular frame 606, an edentulous fork 608, a centric relationrecorder 610 and an orbital pointer 612. The central bar 602 ispositionable through a plurality of clamping assemblies 614, 616, 618,620. The clamping assemblies 614, 618, 620 adjustably position thenasion pointer 604, the edentulous fork 608, and the centric relationrecorder 610 respectively. The central bar 602 is normal to the groundin a direction indicated by axis-Y. The nasion pointer 604 is adjustablypositionable through a first clamping assembly 614 to the central bar;the semi-circular frame 606 is adjustably positionable by the springaction of the semi-circular frame and it is attached to the central barthrough the second clamping assembly 616. The edentulous fork 608 isadjustably positionable through a third clamping assembly 618, and thecentric relation recorder 610 is adjustably positionable through afourth clamping assembly 620. The first clamping assembly 614 clamps thenasion pointer 604 to the central bar 602, the second clamping assembly616 clamps the semi-circular frame 606 to the central bar 602, the thirdclamping assembly 618 clamps the edentulous fork 608 and the fourthclamping assembly 620 clamps the centric relation recorder 610. Thenasion pointer 604, the edentulous fork 608 and the centric relationrecorder 610 are clamped such that the nasion pointer 604, theedentulous fork 608 and the centric relation recorder 610 are positionedalong a predefined axis and are perpendicular to the axis-Y of thecentral bar.

The semi-circular frame 606 is attached such that the central bar 602 isanterior to the semi-circular frame 606 and the semi-circular frame ispositionable by the spring action of the semi-circular frame. Thesemi-circular frame 606 includes two extreme ends, a left end 606A and aright end 606B. The orbital pointer 612 is positioned at a predefinedposition on the semi-circular frame 606 in close proximity of the rightend 606B. The nasion pointer 604, the edentulous fork 608, the centricrelation recorder 610 are attached such that they are adjustablypositionable along a predefined Z axis through the clamping assemblies614,618,620 respectively and are perpendicular to the Y axis of thecentral bar 602 facing towards the two extreme ends 606A and 606B of thesemi-circular frame 606. It is to be noted that the device 600 has twocombinations of reference points, wherein the first combination includesthe two extreme ends 606A and 606B of the semi-circular frame 606 actingas the two posterior points of reference and the nasion pointer 604acting as a first anterior point of reference depending upon the type ofarticulator used. Similarly, the second combination is the two extremeends 606A and 606B of the semi-circular frame 606 acting as the twoposterior points of reference and the orbital pointer 612 acting as asecond anterior point of reference depending upon the type ofarticulator used. The device 600 of the present invention includes apair of recorder, wherein the fourth clamping assembly 620 having thecentric relation recorder 610 acts as the first recorder for recordingthe centric relation and the semi-circular frame 606 along with the twocombinations of reference points acts as a second recorder for recordingof orientation jaw relation of the edentulous subject.

Now referring to FIG. 6B, the third clamping assembly 618 of the device600 for edentulous subjects is described. The third clamping assembly618 includes plurality of screws, a lock 622 and a connector 624 foradjustably clamping the edentulous fork 608 to the central bar 602. Thethird clamping assembly 618 includes the lock 622, the connector 624, afirst screw (not shown), a second screw 626 for horizontal adjustment, athird screw 628 for forward and backward adjustment, and the edentulousfork 608. The edentulous fork 608 includes two ends, a first curved endhaving a C-clip 630 and a second straight end 632. The first curved endof the fork 608 fixedly attaches the C-clip 630 at a predefined positionand the second straight end 632 of the fork 608 is receivable in thelock 622. The C-clip 630 is coupled to the curved end of the fork 608 bya cap 634 such that the cap 634 clamps the C-clip 630 and connects theC-clip 630 to the fork 608 and the respective screws 626 and 628adjustably tighten the edentulous fork 608 according to a predefinedrequirement.

A one end of the connector 624 is horizontally receivable in the lock622 at a predefined position and a other end of the connector 624 isreceivable in a first lock (not shown). The first lock receives thecentral bar 602 and that is lockable by first screw such that theconnector 624 is perpendicular to the central bar 602 and is adjustablein horizontal direction. The lock (not shown) is fixed to the centralbar 602 with the respective screw (not shown). The edentulous fork 608is clamped such that the edentulous fork 608 is perpendicular to theY-axis of the central bar 602. The edentulous fork 608 is adjustable inthe horizontal direction along Z-2 axis by adjusting screw 626 and theforward and backward direction at a predefined position by adjusting therespective screw 628 to achieve a required length. The required lengthof the edentulous fork 608 is achieved by forward and backward movementof the second straight end 632 by loosening of the screw 628 and theedentulous fork 608 is locked at a predefined position as required bytightening of the respective screws.

The C-clip 630 of the edentulous fork 608 facilitates the fastening tomaxillary and mandibular wax rims that are well known in the art. Theedentulous fork 608 for the edentulous subjects is designed in such away that it gets inserted in maxillary and mandibular wax rimsanteriorly in the midline and can be sealed together.

In operation, referring to FIGS. 1 to 5, in a first step adjusting theadjustable fork 108 by loosening the screw 418 such that the two arms416 of the adjustable fork do not come in between the subject'smaxillary and mandibular teeth. Once the adjustment is done, wrapping adouble layer of modelling wax or any other suitable recording materialonto the adjustable fork 108 supporting the recording material fromsides, followed by keeping it aside. In a next step, orienting thesemi-circular frame 106 along the anterior side of the subject's facesuch that the pair of ear plugs 304 are inserted into the subject'srespective ear and approximating the orbital pointer 112 accordingly ina predefined position at the level of infraorbital notch and thesemi-circular frame 106 is parallel to the inter-pupillary line. For thearticulators which need to be adjusted by using nasion as the thirdpoint of reference, a nasion pointer 104 is also provided.

It is to be noted that a subject's anterior occlusal jig is to be madeby either acrylic resin or any other suitable material so that thesubject's maxillary and mandibular teeth do not contact each otherduring any movement of the mandible, i.e., forward, backward and lateraletc. Further step includes fixing the centric relation recorder 110 overthe subjects chin by adjusting the calibrated rod 508 as much aspossible to a required length to ensure that the reading on thecalibrated slider 510 is zero. This is followed by tightening of thescrew 507 to fix the rod 508 and rotating 506 until a firm resistance isfelt by the operator. Further step includes noting of the readings onboth the calibrated rod 508 as well as the calibrated slider 510. Thisprocedure is to be repeated preferably three times by keeping theocclusal jig in place to obtain a mean reading. A simultaneous stepincludes preparing the arms 416 of the adjustable fork 108 with doublelayer wax and softening of the wax or any other preferred material. Nextstep includes placing the centric relation recorder 110 again topreviously noted reading without the occlusal jig by instructing thesubject not to close his teeth. Once the predetermined reading isachieved, asking the subject to open his jaws so that operator caninsert the adjustable fork 108 and instruct the subject to close in onego.

Ensuring that the semi-circular frame 106 is parallel to inter-pupillaryline and it is firmly secured in the ears and then tighten the screw410,412 in order to fix the adjustable fork 108. It is to be noted thatif the articulator is designed to be adjusted with nasion referencepoint as third point of reference, there is no need to adjust orbitalpointer 112, however the nasion pointer is fixed over the nose bridgeand the respective screws are tightened. If, the articulator is designedto be adjusted with infra-orbital notch as a third reference point thennasion pointer need not be used. At this point, ensuring that all therespective screws are tightened and the orbital pointer 112 correspondsto the infra orbital notch, alternatively nasion pointer, if that is tobe used as the third point of reference.

In a next step, loosening of all the respective screws of the centricrelation recorder 110 and separating the clamping assembly from thecentral rod 102 by loosening screw 505. This is followed by looseningthe nasion pointer 104 and/or the orbital pointer 112 and removing thesemi-circular frame 106 that is around the anterior of the subject'sface such that the ear plugs 304 are removed from the subject's earsalong with the adjustable fork 108 having recorded indentations on tothe recording wax material or any other suitable material which can getperforated wherever teeth come in contact.

Further step involves transferring of the obtained recorded indentationsof the wax material to the semi adjustable articulator. For directfacebow transfer the semi-circular frame 106 is placed over thearticulator along with adjustable fork 108 with recorded indentations ina conventional way. Maxillary and mandibular cast are correctly securedinto the recorded indentations obtained from the subject. The thirdpoint of reference either nasion or infra-orbital indicator is used fororientation on the articulator. For indirect transfer, the semicircularframe 106 is separated from the central rod 102 along with the assembly114 and the recorded indentations are transferred to the semi adjustablearticulator using a transfer jig of the articulator. Now the central rod102 along with the assembly of adjustable fork 108 and screws 118 arefixed to the transfer jig of the semi adjustable articulator. Both, themaxillary and mandibular casts are further correctly oriented into theindentations obtained from subject. The mandibular cast is supportedwith modelling clay or carding wax. The maxillary cast is mounted withdental plaster. The articulator is reversed and mandibular cast ismounted. It is to be noted that the records obtained by using the device100 can also be transferred to non-adjustable articulators known in theart.

In another embodiment, a method of using the device 600 of the presentin edentulous subjects is disclosed. Adjusting of the vertical relationis required before using this device 600. There should not be gapbetween the maxillary and mandibular wax rims at occlusal verticaldimension. In a first step, orienting the semi-circular frame 606 alongthe anterior side of the subject's face such that the extreme ends 606Aand 606B of the semi-circular frame 606 are inserted into the subject'srespective ear.

In a next step, asking the subject to relax his/her mandible completelyand fix a arcuate grip of the centric relation recorder 610 exactly overthe center of the chin such that the chin of the subject is in a relaxedposition on the second straight end of the centric relation recorder610. Fixing of the arcuate grip of the centric relation recorder 610over the center of the subject's chin and adjusting the required lengthof the second straight end of the centric relation recorder 610 bytightening the respective screw such that a strong resistance is felt bythe operator. The centric relation recorder 610 is adjusted in forwardand backward motion and is fastened using the screw 507. At the point ofresistance, recording of the respective readings on the calibratedslider and rod of the centric relation recorder 610 is done. In order toobtain a mean reading, repeating the aforesaid disclosed step for atleast three times and recording the readings.

After confirming that the readings are repeatedly same, asking thesubject to maintain the mandible in same position, followed by insertingthe edentulous fork 608. Designing of the edentulous fork 608 foredentulous subjects is done in such a way that C-clip 630 gets insertedin maxillary and mandibular wax rims anteriorly in the midline and canseal it together. In case of edentulous centric jaw relation recordingdevice 600, the subject is not required to open his/her jaw, howeveronly requires the insertion of the edentulous fork 608 to seal both therims together in the anterior region in the midline. In order to sealboth the rims perfectly, normal stapler pins are inserted additionallyon either side buccally, such that half of the pin gets inserted inmaxillary wax rim and half gets inserted into mandibular wax rim. Thetips of the stapler pins can be inserted easily by heating it slightlyover the flame before inserting. Ensure that the semi-circular frame 606is parallel to inter-pupillary line and it is firmly secured in the earsand then tighten the respective screws in order to fix the edentulousfork. If the articulator is designed to be adjusted with nasionreference point as a third point of reference, there is no need toadjust orbital pointer, the nasion pointer is fixed over the nose bridgeand the respective screws are tightened. If the articulator is designedto be adjusted with infra-orbital reference point then orbital pointershould correspond with the infra orbital notch and tighten its screws.At this point, ensuring that all the respective screws arc tightened.

In a further next step, loosening of all the respective screws of thecentric relation recorder 610 and separating the clamping assembly fromthe central rod by loosening screw located behind the bush 620. Thenloosening the nasion pointer 604 and the orbital pointer 612 andremoving the semi-circular frame 606 that is around the anterior of thesubject's face such that the ear plugs 606A and 606B are removed fromthe subject's ears along with the edentulous fork 608 with its sealedmaxillary and mandibular wax rims.

Next step involves transferring of the obtained recorded seal wax rimsto the semi adjustable articulator. For direct facebow transfer, takingthe semi-circular frame with maxillary and mandibular rims attached tothe edentulous fork 608 and then maxillary and mandibular casts areplaced into the respective rims correctly, then using third point ofreference orient the semi-circular frame correctly on the articulator,mandibular cast to be supported by modelling clay and mount it accordingto a preferred method known in the art. For indirect facebow transfer,separating the semi-circular frame 606 from the central rod 602 alongwith the assembly 614. The central rod 602 along with the assembly ofedentulous fork and screws 618 are fixed to the transfer jig of the semiadjustable articulator. Both, the maxillary and mandibular casts arefurther correctly oriented into the sealed maxillary and mandibularrecord bases. The mandibular cast is supported with modelling clay orcarding wax. The maxillary cast is mounted with dental plaster. Then thearticulator is reversed and mandibular cast is mounted.

It is to be noted that the centric relation records obtained by usingthe device 600 can also be transferred to non-adjustable articulatorsknown in the art in case of edentulous subjects. In case of transfer ofthe records on semi-adjustable articulator, condylar guidance can beadjusted by making an interocclusal protrusive record at 6 mm forwardposition of the mandible from the readings recorded at centric relationposition, wherein the mandibular wax rim is reduced by 2-3 mm in height,except in second molar region on either side and in the central incisorsregion for maintaining the vertical dimension. Inverted ‘V’ shapednotches are prepared on the maxillary wax rim in premolar and firstmolar region on either side. To obtain a protrusive reading 6 mm issubtracted from the said centric relation reading where a firmresistance was felt by the operator. The centric recorder assembly isfixed at said predefined protrusive reading and the recording materialsuch as plaster of Paris or any other suitable material is placedbetween the wax rims and the condylar guidance is adjusted according tosaid protrusive record. Further the lateral condylar guidance can beadjusted by using Hanau's formula L=H/8+12 which is known in the art.

In a preferred embodiment, device 100 and 600 for recording centric jawrelation and orientation jaw relation simultaneously of the presentinvention can also be used to perform orientation jaw relation orface-bow transfer such that, the recording of the centric jaw relationand orientation jaw relation is achieved in the single step, therebyavoiding multiple sittings or appointments. The device 100 and 600 forrecording centric jaw relation and orientation jaw relation of thepresent invention helps in recording of the centric jaw relationaccurately, and that has improved ergonomics and a user friendly design.The devices in the prior art fail to provide accurate centric jawrelation recording and that there is no simple device as that like thepresent invention which can record the complicated centric jaw relation.The device 100 and 600 advantageously include two combinations ofreference points, namely first combination with nasion pointer andsecond with orbital pointer, which makes the device of the presentinvention novel. There is no device in art with two combinations ofreference points and one can use any of the predefined combination ofreference point depending upon the type of articulators used and canrecord centric relation. The device 100 and 600 of the present inventionis applicable for any conventional semi-adjustable or non-adjustablearticulators. The third point of reference may not be required in caseof non-adjustable articulators. Further, in case of edentulous subject,the condylar guidance can be adjusted by making an interocclusalprotrusive record obtained at 6 mm forward position of the mandible fromcentric relation reading. The present invention eliminates the drawbacksof the methods and devices disclosed in the prior art and provide ahighly efficient and simple device with enhanced ease and comfort inoperation, thereby reducing chances of injury to subject and providesimproved efficiency in recording centric jaw relation and in achievingefficient face bow transfer. The device 100 and 600 of the presentinvention also reduces the number of appointments and thereby saves lotof time.

The purpose of the device 100 and 600 of the present invention is notonly to simplify recording of centric jaw relation as per thedescription given in the glossary of prosthodontics (GPT)-8 but to makeit a simple mechanical procedure where any dental surgeon can record aperfect centric jaw relation irrespective of whether the subject isdentulous or edentulous. The device 100 and 600 of the present inventionis the first mechanical device which guides the condylar head in itscentric jaw relation position as described in its definition. Presentinvention is designed to record the orientation jaw relation also andfurther it can be transferred to the articulator in the same sitting,thereby minimizing multiple visits otherwise required. The device 100 ofthe present invention for recording centric jaw relation and orientationjaw relation simultaneously of dentulous subjects and device 600 forrecording centric jaw relation and orientation jaw relationsimultaneously of edentulous subjects is the unique device based on thelatest definition of centric jaw relation as per GPT-8. The device 100for recording centric jaw relation for dentulous subjects and device 600for edentulous subjects of the present invention advantageously helps inan accurate and precise recording of the centric jaw relationmechanically.

The device 100 for recording centric jaw relation and orientation jawrelation simultaneously for dentulous subjects and device 600 of thepresent invention is designed in such a way that gives maximum comfortto the subjects. The device 100 for dentulous subjects and device 600for edentulous subjects of the present invention guide the mandible insuch a way that the head of the condyle in the glenoid fossa, along withits respective complexes, will attain most anterior and superiorposition on either side which is the centric jaw relation position. Thedevice 100 for dentulous subjects and device 600 for edentulous subjectsof the present invention is the only face bow compatible device with anyexisting articulators using different third points of references, i.e.,nasion and infraorbital notch. The device 100 for dentulous subjects anddevice 600 for edentulous subjects of the present invention provides anunique semi-circular frame that gives a better spring action that helpsin improved stabilization of the semi-circular frame over the subject'sface.

The device 100 for recording centric jaw relation for dentulous subjectsof the present invention provides an adjustable fork for dentuloussubjects that is designed to record maxillary and mandibular occlusalrecord without any interference of the teeth, thereby customizing thebite adjustable fork according to the width of the subject's arch. Thedevice 100 for dentulous subjects and device 600 for edentulous subjectsof the present invention is the only device which records centric jawrelation as per the new definition of CR (GPT-8).

A person skilled in the art will appreciate that the device of thepresent invention if used according to the process disclosed above isvery easy to use and is not cumbersome relative to the devices usinggraphical methods of the prior art. It will be further appreciated thatthe device of the present invention has got high adaptability among thelearners because of the novel structure and standardized operational useas disclosed in the present invention.

The embodiments of the invention shown and discussed herein are merelyillustrative of modes of application of the present invention. Referenceto details in this discussion is not intended to limit the scope of theclaims to these details, or to the figures used to illustrate theinvention.

1. A device for recording centric jaw relation and orientation jawrelation simultaneously of an edentulous subject in a single stepcomprising: a central bar; a first recorder comprising a semi-circularframe adjustably positionable on the central bar through a firstclamping assembly, the semi-circular frame having a first end and asecond end defining a pair of posterior reference points relative to thefirst clamping assembly of the semi-circular frame secured to thecentral bar; a centric relation recorder including, comprising acalibrated rod, a calibrated slider and an arcuate grip, the calibratedrod having a predefined first main scale and the calibrated sliderhaving a predefined second scale for recording a centric jaw relation ofthe edentulous subject through the arcuate grip thereby adjustingaccording to the first main scale and the second scale of the calibratedrod and the calibrated slider, respectively, the calibrated slider beingfreely movable within the calibrated rod along a predefined axisthereof; an edentulous fork having a curved first end and a straightsecond end, the curved first end having a C-clip attached at apredefined position through a cap, the C-clip facilitating fastening tomaxillary and mandibular wax rims in a midline of the edentuloussubject, and the second straight end adjustably positionable to thecentral bar through a second clamping assembly; a nasion pointer, thenasion pointer defining a first anterior point of reference; and anorbital pointer, the orbital pointer defining a second anterior point ofreference.
 2. The device as claimed in claim 1, wherein the centricrelation recorder, the nasion pointer and the edentulous fork areperpendicular to the central bar.
 3. The device as claimed in claim 1,wherein the centric relation recorder, the nasion pointer and theedentulous fork are adjustably positioned at a predefined position onthe central bar.
 4. The device as claimed in claim 1, wherein theorbital pointer positions at a predefined location on the semi-circularframe such that the semi-circular frame is parallel to aninter-pupillary line of the edentulous subject.
 5. A method forrecording centric jaw relation and orientation jaw relationsimultaneously of an edentulous subject, said method comprising thesteps of: a. recording correct vertical jaw relation thereby ensuring nogap between maxillary and mandibular wax rims at occlusal verticaldimensions thereof; b. orienting and stabilizing a semi-circular framealong an anterior side of the subject's face thereby approximating anorbital pointer in a predefined position at a predefined level ofsubject's infraorbital notch or alternatively nasion pointer in apredefined position over the nasion depending on the semi-adjustablearticulator being used; c. fixing a centric relation recorder over thesubject's chin by adjusting a predefined calibrated rod and a predefinedcalibrated slider; d. noting the readings on the calibrated rod andcalibrated slider by following the steps (c) at least three times; e.designing of a fork for edentulous subjects by inserting said fork inmaxillary and mandibular wax rims anteriorly along a midline thereof; f.the centric relation recorder back to the noted reading of step (d) andan edentulous fork is inserted in the midline in such a way that itseals maxillary and mandibular wax rims together; g. sealing both therims together additionally by stapler pins by placing it on either sidebuccally such that half of the pin inserting into the maxillary wax rimand half of the pin inserting into the mandibular wax rim; j. tighteningthe nasion pointer, the edentulous fork and centric relation recorder byrespective screws such that orbital pointer corresponding to the infraorbital notch or alternatively the nasion pointer corresponding to thenasion thereby defining a third point of reference; k. loosening allrespective screws of the centric relation recorder and the nasionpointer followed by removing the semi-circular frame of the subject'sface along with the edentulous fork having sealed maxillary andmandibular wax rims; h. transferring the recorded sealed wax of step (g)to the semi adjustable articulator either by direct transfer or indirecttransfer; i. after transferring centric relation record and mounting ofthe casts to said articulator, recording of a protrusive record foradjusting the condylar guidance on a semi-adjustable articulator isdone, wherein; reducing the mandibular wax rim by 2-3 mm in height,except in second molar region on either side and in the central incisorsregion for maintaining the vertical dimension; preparing inverted ‘V’shaped notches on the maxillary wax rim in premolar and first molarregion on either side; subtracting 6 mm from said recorded centricrelation reading when a firm resistance was felt by the operator,thereby obtaining a protrusive reading of an edentulous subject; fixingcentric recorder assembly at said predefined protrusive reading andplacing the recording material such as plaster of Paris or any othersuitable material between the wax rims; and adjusting the condylarguidance according to said protrusive record and adjusting a lateralcondylar guidance by using Hanau's formula L=H_/8+12.
 6. The device asclaimed in claim 1, wherein said device records the centric relation andorientation jaw relation simultaneously and said device also recordseither centric relation or orientation jaw relation separately as perthe requirement.
 7. The device as claimed in claim 1, wherein thecentric relation record is transferred to any semi-adjustablearticulators or non-adjustable articulators.